An image forming apparatus is known which forms an image on a recording medium by transferring transfer materials in sequence from a plurality of transfer material regions that are formed on a belt-like transfer medium in a repeated manner along its longitudinal direction. Specifically, an image forming apparatus is known which, after forming an image with a size not larger than one half the transfer material region size by partially using each of the transfer material regions, can form a new image with the same size by rewinding the transfer medium and using the unused portions of the partially used transfer material regions.
For example, patent document 1 discloses a thermal transfer color printer which, when performing L-size printing by using a 2L-size ink ribbon, uses the ink ribbon in the reverse direction starting from the end of each ink region of the ink ribbon (in the rewinding direction of the ink ribbon), rather than in the usual forward direction starting from the beginning of each ink (in the winding direction of the ink ribbon).
On the other hand, patent document 2 discloses a printer which has the capability to print a plurality of images smaller in size than the surface of an ink layer of an ink ribbon, and which, based on the average grayscale value of the previously printed image, assesses the magnitude of thermal damage that the ink ribbon suffered and, when printing the next image, performs control by determining whether to rewind the ink ribbon and use the remaining unused portions or to use new portions of the ink ribbon.